webui: automation settings panel, set-location, responsive layout

- Automation tab: settings form (define_settings) beside the editor,
  stacking above it when narrow; script/settings save split.
- Set location modal: current location + reset checkbox.
- saveScriptSettings/setSavePath API wiring; plugins panel.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

public/js/api.js

@@ -11,10 +11,16 @@ async function jpost(url, body) {
     headers: { 'Content-Type': 'application/json' },
     body: JSON.stringify(body || {}),
   });
+  if (!r.ok) throw new Error(`${url} → ${r.status}`);
   return r.json();
 }
 
 export const api = {
+  authStatus: () => jget('/api/auth/status'),
+  login: (username, password) => jpost('/api/login', { username, password }),
+  logout: () => jpost('/api/logout', {}),
+  plugins: () => jget('/api/plugins'),
+
   meta: () => jget('/api/meta'),
   snapshot: () => jget('/api/snapshot'),
   torrent: (hash) => jget(`/api/torrents/${hash}`),
@@ -35,6 +41,9 @@ export const api = {
 
   rss: () => jget('/api/rss'),
   rssRules: () => jget('/api/rss/rules'),
+  script: () => jget('/api/script'),
+  saveScript: (source) => jpost('/api/script', { source }),
+  saveScriptSettings: (settings) => jpost('/api/script/settings', { settings }),
   search: (q) => jget(`/api/search?q=${encodeURIComponent(q)}`),
 
   // Live snapshot stream. onSnapshot(snapshot) called ~1/s.